t = time to hike up the hill
3-t is the time to hike down the hill
 so 4t = 6(3-t)
4t = 18-6t
10t = 18
t = 18/10 = 1.8 hours to hike up the hill
1.8 hours = 1 hour 48 minutes
Answer:
The time it took him to climb up the hill is 1.8 hours.
Step-by-step explanation:
Here, t represents the the time it took him to climb up the hill,
Total time taken by it = 3 hours,
Thus, the time taken by it to climb down the hill = ( 3 - t ) hours.
Since, Trent hikes up a hill at 4 km/h,
⇒ Total distance covered by it to climb up = 4 t   (Distance = Speed × Time)
Since, Trent go down a hill at 6 km/h,
⇒ Total distance covered by it to go down = 6(3-t) Â
We know that,
Total distance covered by it to climb up = Total distance covered by it to go down
⇒ 4t = 6(3-t)
Which is the required equation.
⇒ 4t = 18 - 6t
⇒ 10 t = 18
⇒ t = 1.8
Hence, the time it took him to climb up the hill is 1.8 hours.
